Conventionally, the vehicle sensitive locking retractor, both with and without comfort mechanisms, are found in most current automotive vehicles. In general, the vehicle sensitive retractor structure involves a pendulum or other inertial structure which reacts to sudden acceleration, impact or deceleration and braking to cause a physical locking of the retractor against withdrawal of additional webbing. Typically, an inertial structure acts to move a lock pawl into stop engagement against a ratchet operably driven by the spool or reel of the retractor. This is an effective safety restraint for passengers and allows a freedom of movement not found in prior art automatic locking retractors. This occurs because the pawl is not placed in contact with the ratchet until the acceleration or deceleration reaches a selected value. Then, the vehicle sensitive lock acts in prevention of further withdrawal. However, in securing cargo, children's safety seats, and children's seat belts, it is important to set the webbing against the object or child and then rely upon the webbing to retain the locked position against any further withdrawal. Then, when the retractor is used with adults, it functions as a vehicle sensitive locking retractor. Something of this sort was accomplished in the U.S. Pat. No. 4,402,473 to Tatsushi Kubota and Mitsuaki Katsuno, and also in the U.S. Pat. No. 4,427,164 to Robert J. Rumpf. In those devices, manual control was provided to override the vehicle sensitive mechanism and to apply a bias against a pawl urging it into lock engagement with the ratchet structure. The principal limitation of such devices was in the fact that manual access to the retractor was necessary. If direct access was not possible, then a solenoid or mechanical linkage for remote manipulation of the pawl bias is required at the retractor. The device of Katsumi Naitoh in U.S. Pat. No. 4,428,545 characterizes the remote manipulative control over an automatic locking structure.
In the retractor device of the present invention, the vehicle sensitive locking function is disabled and the automatic locking function is engaged simply by self-actuation upon selected withdrawal of seat belt webbing to a point somewhat beyond normal usage. Then the retracting of the surplus webbing to the selected use around, say, the body of an infant, results in the locking of the webbing against any further withdrawal. Then, upon unbuckling and releasing the webbing, the automatic locking retractor feature is disabled and the vehicle sensitive inertial locking feature is restored.
This is achieved very simply and economically without the requirement for external circuitry or cable and remote manipulative paraphernalia. It is useable in dual spool and tandem spool arrangements without departure from the concept as applied to a single spool retractor. It is especially important where access to the retractor is not manually feasible but where the buckle belt or tongue secured to the end of the webbing is presented to the user in a convenient manner.